Train Low. Race High. - Page 2

Into Thin Air

It's nearly impossible to dispute the physiological effects of running at altitude, and few people are more qualified to spell them out than Jack Daniels, Ph.D. Daniels is Head Distance Coach at The Center for High Altitude Training at Northern Arizona University. He has coached 31 individual NCAA National Champions and 131 All Americans. He was also named the NCAA Cross Country Coach of the Century and was the altitude consultant for the USATF team at the 1968 Olympic Games in Mexico City (elev. 7349 feet).

There is one cold, hard, non-negotiable truth to high-altitude mountain running: there is no substitute for training high. "Outside of running on a treadmill in a pressure chamber," says Daniels, "there's not much you can do [at sea level]." But don't be discouraged—there are training and tactical options that can make a difference.

"The main issue is the higher you go the lower the barometric pressure," says Daniels. "Each liter of blood carries less oxygen than at sea level, and the amount of work you can do is less."

That is why lower-altitude runners may feel fine early in a race, but fatigue sooner than someone properly acclimatized. And the higher the altitude, the greater the effects.

Between sea level and 2000 feet, there is no difference in athletic performance, explains Daniels. In fact, the difference between running at 2000 feet and 5000 feet is not major, either, and that is welcome news to runners eyeing races in lower peaks, such as the Appalachians.

"The difference between 5000 and 7000 feet is the same as between sea level and 5000," says Daniels. "Above 10,000 feet, performance drops off real fast."

This accounts for many stories of runners performing moderately well up to a certain altitude, then hitting a wall. When they drop below that threshold, their energy returns.

Timing Is Everything

Janet Hamilton, a registered clinical exercise physiologist near Atlanta, has also studied the effects of high altitude on athletes. "If you can't get to altitude several months in advance -- that is, if you have a job and a life," she says, "your next-best choice is to run the event within 24 hours of arriving."

Here's why. At altitude, there is less oxygen being bound to the hemoglobin in red blood cells. When your body recognizes this, its response is to hyperventilate—breathe more—in an attempt to collect more oxygen. Its next effort is "hemo-concentration," where it "dumps" plasma (essentially the fluid portion of your blood). This occurs through the body's natural fluid loss at altitude.

The good news is that hemo-concentration results in a higher concentration of oxygen in the blood. The bad news is that the blood becomes more viscous, making it harder to move throughout the bloodstream—a major problem during a race.

"That process of hemo-concentration takes a little over 24 hours," says Hamilton, "And the only way the body can eventually deal with this dilemma is to slow you down."